<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Test13</title>
</head>
<body>
    <script type="text/javascript">
        var a = prompt("请输入一个数字");
        alert(a%2==0?"偶数":"奇数");
    </script>
</body>
</html>